“The dynamo burned out,” Bart answered. “I just coupled in the spare one. Where have you been?” “Out on the skin,” Steve said. “I was trying to signal Jim Dennis.” Bart’s face went red again, and he muttered to himself. “I didn’t think there was any chance of repairing the trouble,” Steve went on. “I’d rather burn than take help from Jim Dennis!” Bart snapped. “Did Dennis see you?” “He must have. He went right overhead.” “Obviously he didn’t stop, though.” “No, he didn’t,” Steve said frankly. “I wouldn’t have believed that of Dennis,” Bart murmured. “I thought he was a better man than that.” “He may not have seen me, Bart. Let’s give him the benefit of the doubt.” “I’ll give him nothing!” Bart rapped. “If Jim Dennis wants a fight to the finish, we’ll give it to him!” Bart began immediately to battle to regain their lead. It was a frenzied, closely fought contest for many hours, the lead seesawing back and forth. It took the top speed Bart’s craft was capable of to gain the lead he was finally able to maintain. Only when Jim Dennis appeared content to linger behind again did Bart cut their driving velocity. Once more Steve felt he could breathe easier—for a while at least. In the days that followed, there were no changes in position. Steve and Bart took turns at the controls during the sleeping periods. They could see the planet Venus at a distance. Their flight had been planned to avoid close proximity with Earth’s twin because of the retarding effect of her gravity. The sun steadily dominated the sky, an enormous cottony ball of atomic fury with a surface temperature of 6000 degrees centigrade and an interior heat around 20,000,000 degrees. The red leaping flames of the chromosphere were like the mountainous waves of a gigantic cosmic ocean as they lapped millions of miles out into surrounding space. Magnetic storms—sunspots—all of them large enough to swallow the Earth, were seen as whirling dark cyclones in the sea of gas. As the _Condon Comet_ moved around and behind the star, it began to close in on the planet Mercury. The ship was actually overtaking the miniature world even though it was circling the sun at a rapid thirty miles a second. On the fifth day away from Earth, the _Condon Comet_ reached its apogee, the farthest point of its orbit from the mother planet. It was “behind” the sun now, the dominant ball eclipsing the Earth. By now Mercury had grown hugely, a big pebbly world that literally shimmered with the frightening heat that poured down upon it. It was a startling sight, halved into hemispheres of darkness and extreme brilliance. The closer side was so hot that streams of molten tin and lead flowed, while that side away from the sun approached the arctic cold of absolute zero. “I hope we don’t have to land there, Bart,” Steve spoke uncomfortably, looking out the port.